Cleaning apparatus

ABSTRACT

A system for removing accumulations of liquid and fine solid materials from between two movable contacting members that seal the accumulated materials in a slot where they are blasted by air to a receptacle. The blast is timed to occur when the slot is sealed between the member which carries it and a second member moving over it. An actuator releases air when the slot is sealed.

United States Patent Egnaczak 1 July 4,1972

[54] CLEANING APPARATUS [72] Inventor: Raymond K. Egnaczak, Williamson, NY.

[73] Assigneei Xerox Corporation, Rochester, N.Y.

221 Filed: Nov. 14, 1969 [21] Appl. No.2 876,715

[52] US. Cl ....15/316, 134/37 [51] Int. Cl ..B08b 5/00 [58] FieldoiSearch ..134/1,9,21,37;117/102 A,

117/111 F, 37 LE; 15/306, 306 A, 302, 308, 309, 316; 118/637; 355/15 [56] References Cited UNITED STATES PATENTS 1,908,519 5/1933 Leonard ..100/174 X 1,814,866 7/1931 Stride ..l5/302X 3,003,176 10/1961 Goyette ..l5/308X Primary Examiner-Morris O. Wolk Assistant Examiner-Joseph T. Zatarga Attorney-James J, Ralabate, David C. Petre and Barry Jay Kesselman [57] ABSTRACT A system for removing accumulations of liquid and fine solid materials from between two movable contacting members that seal the accumulated materials in a slot where they are blasted by air to a receptacle. The blast is timed to occur when the slot is sealed between the member which carries it and a second member moving over it. An actuator releases air when the slot is sealed.

9 Claims, 4 Drawing Figures PATENTEDJUL M972 3.673.632

sum 10F 4 7 9 I I I I 2 INVENTOR. RAYMOND K. EGNACZAK A TTORNEV PATENTEDJUL 4 I972 SHEET 4 BF 4 CLEANING APPARATUS This invention relates to cleaning systems and in particular to cleaning systems for removing accumulated materials from between two members.

Apparatus exists today where materials applied to a member of the apparatus tend to accumulate on it. As the member interfaces with other devices moving relative to it, the materials are pushed ahead of the interface area. What generally happens with a liquid and some solid materials is that a major portion of the material is pinched ahead of the nip between the two moving members forming a bead or a large accumulation at the lead edge in the direction of approach of the members. If the bead is allowed to accumulate in front of the approaching devices, it may have dilatorious effects upon the apparatus in which it is found.ne particular class of apparatus that sometimes encounters this accumulation of materials are hard copy imaging systems. One such system known as photoelectrophoresis is used for forming black and white or full color images. The basic processes and apparatus are disclosed in U.S. Pat. Nos. 3,384,565; 3,384,566 and 3,383,993. Since this discovery, various apparatus have been developed to utilize the process disclosed therein.

The basic system utilizes photoelectrophoretic particles which migrate in image configuration providing a visual image at one or both of two electrodes between which the particles are placed in a suspension. The particles are photosensitive and apparently undergo a net change in charge polarity or a polarity alteration by interaction with one of the electrodes upon exposure to activating electromagnetic radiation. The particles will migrate from one of the electrodes under the influence of an electric field when struck with energy of a wavelength within the spectral response of the particles.

Apparatus has been invented to better utilize the above process in an automated system shown in U.S. Pat. No. 3,427,242 issued Feb. 1 l, 1969 which described a continuous apparatus embodiment of the above process. Further, equipment has been designed utilizing flat and rotary imaging members to form images with the above process all of which can be improved by the invention herein.

Another systemthat can be improved by theinvention described herein is xerographic imaging where an image is formed and developed on the surface-of a photoconductor by electrostatic means. The basic xerographic process as taught by C. F. Carlson in U.S. Pat. No. 2,297,691 involves placing a uniform electrostatic charge on a photoconductive insulating layer, exposing the layer to a light image to dissipate the charge in the areas of the layer exposed to the light and then developing the resulting latent electrostatic image by depositing on the image a finely divided electroscopic material referred to in the art as toner. The toner is attracted normally to those areas of the photoconductive layer which retains a charge thereby forming a toner image corresponding to the electrostatic latent image. The toner image may then be transferred to a support surface and pennanently afiixed thereto by heat or vapor or the like. It may also be that the photoconductive layer itself serves as the final support medium in which case no transfer step is required.

Many varied methods and apparatus have been designed for developing the latent electrostatic image. Among them are liquid development systems. In conventional liquid development systems as insulating liquid vehicle having finely divided solid material dispersed in it contacts the surface in both charged and uncharged areas but is maintained on the photoconductive surface in a relation to the latent electrostatic image charge pattern thereon. Disclosed in U.S. Pat. No. 3,084,043 is a liquid development system known as polar liquid development. Another development technique is disclosed in U.S. Pat. No. 3,285,714 where an aqueous developer uniformly contacts the entire imaging surface and selectively wets only the charged areas of the imaging surface.

The liquid developing techniques as well as some dry development techniques often accumulate excess development materials and carriers along the surface of the photoconductive material. It is with these development systems that the invention described herein is a helpful improvement since the developer liquid is loaded onto the applicator surface indiscriminately in excessive quantities. As the developer liquid on the surface of the applicator is brought into contact with the photoconductive surface, it squeezes into a bead at the exit of the nip between the two surfaces. This material is not fully utilized in forming a visible image on the photoconductive surface and it would be helpful to remove the material at least after an image is formed to prevent residual material from interfering with later images to be formed.

Other apparatus can be contemplated such as schematically shown in FIG. 1 hereinafter which uses segments of cylinders in its operation. If the accumulated materials are allowed to ride along the segment, they will eventually leak, drip or fall into the interior of the segment and interfere with the internal mechanism or general operation of the apparatus utilizing such a cylinder segment. Therefore, it becomes important to eliminate accumulations of materials from reaching the edge of segments of cylinders or from continually revolving around a cylindrical or other shaped members.

Therefore, it is an object of this invention to remove accumulations of materials between moving surfaces.

Another object of this invention is to improve cleaning techniques of imaging systems. Yet another object of this invention is to improve means for the development of images. Still another object of this invention is to remove accumulated powders or liquids from between moving surfaces.

A further object of this invention is to improve systems for removing accumulations of materials between two moving members cyclically and automatically. Another object of this invention is to prevent accumulations of materials from interfering with further images of an imaging system.

These and other objects of this invention are accomplished by providing a timed air blast through a slot on one of two interfacing surfaces. The air blast forces materials trapped in the slot, between the two mated surfaces, along the length of the slot to a container. The air blast is effective when the slotted member is contacted at the slot by another member thereby sealing the slot.

The invention herein is described and illustrated in a specific embodiment having specific components listed for carrying out the functions of the apparatus. Nevertheless, the invention need not be thought of as being confined to such a specific showing and should be construed broadly within the scope ofthe claims. Any and all equivalent structures known to those skilled in the art can be substituted for specific apparatus disclosed as long as the substituted apparatus achieves a similar function. It may be that other processes or apparatus will be invented having similar needs to those fulfilled by the apparatus described and claimed herein and it is the intention herein to describe an invention for use in apparatus other than the embodiment shown.

The above and other objects and advantages of this invention will become apparent to those skilled in the an after reading the following description taken in conjunction with the accompanying drawings wherein:

FIG. 1 schematically illustrates an embodiment of a machine for forming photoelectrophoretic images;

FIG. 2 is a side view of .the member embodying the invention with hidden parts dotted;

FIG. 3 is a sectional view taken along line 33 of FIG. 2; and

FIG. 4 is a front view of the member with he drive and actuation apparatus sectioned.

A detailed description of the operation and theories pertaining to the actual imaging system shown in FIG. I are described in the U.S. Pat. Nos. 3,384,488; 3,384,565; 3,384,566 and 3,383,993 referred to above. Certain terms referred to therein are adopted herein such as the injecting electrode" so named because it is thought to inject electrical charges into activating photosensitive particles during imaging. The term "photosensitive" refers to the property of a particle which, once attracted to the injecting electrode will alter its polarity and migrate away from the electrode under the influence of an applied electric field when exposed to activating electromagnetic radiation. The term suspension" is used here to refer to a solid suspendedin a liquid carrier. The term imaging electrode describes that electrode which contacts the injecting electrode through the suspension and which once contacted by activated photosensitive particles will not inject sufficient charge into them to cause them to migrate from the imaging electrode surface. The imaging zone is that zone between two electrodes where photoelectrophoretic imaging occurs.

Briefly, for photoelectrophoretic imaging to occur these steps take place: (1) migration of the photosensitive particles toward the injecting electrode due to the influence of an external field, (2) generation of charge carriers within the particles when struck with activating radiation, (3) particle deposition or near the injecting electrode surface, (4) phenomena associated with the forming of an electrical junction between the particles and the injecting electrode, (5) particle charge exchange with the injecting electrode, (6) electrophoretic migration toward the imaging electrode and (7 particle deposition on the imaging electrode. Thisleaves a positive image on the injecting electrode.

THE MACHINE COMPONENTS Referring now to FIG. 1, a preferred embodiment for an automated machineto produce images according to the aforementioned process is shown. An injecting electrode 1 forms a portion of a transparent cylinder member held in a housing 2 and is journaled for rotation in the direction indicated by the arrow about a shaft 3. Theinjecting electrode 1 is made up of a layer of optically. transparent glass 4 overcoated with a thin optically transparent layer 5 of tin oxide or other electrically conducting material. A particular material suitable for this electrode is available under the name of NESA glass manufactured by Pittsburgh Plate Glass Company, Pittsburgh, Pa. The

injecting electrode 1 is formed as a portion of a cylinder housed within the metal housing frame 2.

The machine shown schematically in FIG. 1 is positioned where the injecting electrode cylinder portion is about to be rotated in a predetermined path to a cleaning station labeled A whereat a plurality of cleaning members such as belts 6, 7 and 8 contact the conductive surface 5 of the injecting electrode. On the opposite'side of the injecting electrode held stationary within the machine frame are lamps 9, 10 and 11 juxtaposed to the belts 6, 7 and 8 respectively. When activated, the lamps send flood light illumination through the transparent injecting electrode at the contact areas between the electrode and the cleaning belts. Each of the belts are activated by one of the cylinders 12, 13 and 14 to contact the injecting electrode 1. These cylinders operate to press the belts against the conductive surface of the injecting electrode in order to clean it.

The next station in the path of movement of the injecting electrode is the imaging station B. Here, on the first pass of the injecting electrode 1 through station B the first imaging member, the imaging electrode 16 interfaces with the conductive surface 5 of the injecting electrode 1.

The optical system at station C projects an image to the imaging zone between the electrodes 1 and 16 at station B. The optical system has a lamp carriage l7 journaled at an axis 18 to oscillate in a path indicated by the arrows. A document 20 is positioned at the platen 19. The lamps are shown at the start of scan position and as the injecting electrode 1 passes through the imaging area at station B the lamps move across the platen 19 projecting an image at station B through suitable mirrors 21-23, a lens 24 and the transparent electrode 1.

The imaging electrode roller 16 moves inrolling interface relation with the conductive surface 5 of .the injecting electrode 1 and functions both to supply suspension to the injecting electrode and to image that suspension between the injecting electrode surface 5 and the surface of the electrode 16.

The injecting electrode continues to rotate at a constant velocity through a complete rotation of the predetermined path. It travels without interacting with any elements located around the periphery of the path until it again reaches station B at the imaging zone. Now, however, the injecting electrode 16 has been moved out of its interfacing position by operation of a cylinder 25 which lowers the electrode 16 and the housing 26 supporting it. Further, a cylinder 27 moves a carriage 28 along a horizontal path carrying with it the housing 26 which supports the imaging electrode 16. Also moved in the carriage 28 is a second imaging member, the imaging electrode 29 a housing 30 maintaining it. A cylinder 31 operates through an eccentric 32 to raise the housing 30 and the second imaging electrode 29 at the imaging zone at the imaging sta tion B of the machine. The second imaging electrode 29 moves in rolling interface with the injecting electrode surface 5 as that surface passes through the imaging station B. At this time the original 20 on the platen l9 is again illuminated by the scanning lamps 33 at the optical system station C. The scan is synchronized with the movement of the injecting electrode to project a flowing image in registration with the first projection and moving at the same rate as is the surface 5 at the imaging zone.

The injecting electrode. 1 then passes into the transfer station D. At station D is a transfer roller 40. A sheet of support material held in the supply tray 41 is lifted therefrom and is carried through a vacuum transport 42 to the transfer roller 40. It is gripped by a gripper mechanism 43 on the transfer roller 40 and rotated to the injecting electrode 1 passing at station D. Before the sheet 44 contacts the surface 5 of the injecting electrode 1 it is moistened with a liquid that will aid in transferring the particles of the suspension on the surface 5.

The wetting is accomplished by a wetting bar 45 rotated in a pool of suitable wetting material held within a tank 46. The transfer member 40 rotates the support material 44 in rolling contact with the surface 5 of the injecting electrode 1 under the influence of a suitable electric field causing the particles forming the image on the injecting electrode to be transferred to the support material. The support material is removed from the transfer member by picker fingers 47 and a release mechanism on the grippers. Next it is carried on a vacuum transport 48 to a fixing station E where it is heated or otherwise fixed to form a pennanently bonded image on the support material which is then deposited in some suitable receptacle.

FIGS. 2 and 3 show the injecting electrode housing and assembly as viewed from the cleaning station A in FIG. 1. The light shield has an aperture slot 146 at the imaging station of the machine. The aperture 146 is a field stop near the image plane of the optical system to limit the image area illuminated at the imaging electrode. At the opposite end of the light shield is an aperture 146 through which the light rays from the optical system pass to reachthe image plane. The light shield is used to prevent ambient light from reaching the imaging station and interfering with the illumination used for forming the images. The light shield, light mounting brackets and those members associated therewith are stationary within the machine and once positioned according to the optical path requirements do not move during the operation of the machine. Rotating around the light shield and the apparatus appended thereto is the injecting electrode and its associated housing.

The injecting electrode is held in an electrode support frame 150. Mounted on he drum frame 150 is an overframe 151.

The frame 150 is rotated about fixed shafts 153 and 154 which fasten to the light shield 145. The ends of the frame 150 are closed by two end caps 155 and 156 which are each mounted on a bearing housing, 157 and 158 respectively, on each side of the assembly. The bearing housing 157 is mounted through bearing 159 to the machine support frame 160 shown dotted herein for reference.

The bearing housing and end cap are mounted to the fixed frame by bearings 162 and 163 to permit rotation of the cylinder frame 150 and injecting electrode around the fixed shaft 153. The fixed shaft 153 has a fiat 164 at the end thereof which for location within the machine support frame 160 to set the aperture 146 in the proper position for imaging at the imaging electrode station.

On the other side of the cylinder frame 150 is the fixed shaft 154. This shaft is in fact a hollow tube permitting air flow therethrough. An air fitting 165 is attached to the outboard end of the fixed shaft to couple to an air supply for bringing air through the hollow portion 166 of the fixed shaft 154. The hollow 166 connects with an angular groove 167 which in turn connects to a slot 168 in the bearing housing 158. O-rings 169 and 170 effectively seal the passage from air leaks during operation of the system. The slot 168 feeds into a piston housing 171 which comprises a backing member 172, an air chamber 173, a piston valve seal 174, piston valve 175 and return spring 176. Also cut into the piston housing 171 is a chamber 177 which connects to the cleanout slot 178 in the glass support member 148.

A register pin 179 is located in a hole within the bearing housing 158. The bearing housing rotates about the fixed shaft 154 through two bearings 180 and 181. The bearing housing 158 is formed from a long hollow tube with a tapered surface 182 near the pin 179. The gear box brings the power supply used for rotating the injecting electrode housing. The nut draws the shaft 187 into tight contact with the taper 182 of the bearing housing 158 and ensures that the slot 188 covers the register pin 179 for positive driving of the injecting electrode drum assembly.

On the gear box 184 is a valve actuator trigger 189 having a solenoid 190 powered by a power supply 190a which is programmed to trigger the piston rod 191 to strike the piston valve 175 causing a burst of air to How through the cleanout slot 178. This sequence occurs when the cleanout slot 178 is contacted by either of the imaging electrodes 16 or 29 or the transfer roll 40 which forms a seal with the slot to ensure that all of the materials forced into the slot will be air blasted completely through and out the other end thereof.

A switch 192 makes a contact when struck by the register pin 179. This actuates the solenoid as described above. A second switch is located to actuate the solenoid when the slot 178 is sealed at the transfer station D when the piston valve 175 is contacted by the piston rod 193 shown in FIG. 2 positioned in the actuator trigger 194.

The materials and air forced through the cleanout slot 178 strike a deflector tube 195 and are carried into a receiver container 196 where the materials can be stored or removed at the will of the machine operator. The gases for operating the system may be supplied by an convenient means such as the air cylinder 197 schematically shown in FIG. 3. Of course, any equivalent functional mechanism can be used and any convenient gases employed. Air and air cylinders are used as illustrations for functional equivalent gases and supply systems.

While this invention has been described with reference to the structures disclosed herein and while certain theories have been expressed, it is not confined to the details set forth; and this application is intended to cover such modifications or changes as may come within the purposes of the improvements and scope of the following claims.

What is claimed is:

1. Apparatus for removing accumulated materials including a member having a slot in the surface thereof;

means for contacting said member at the surface thereof;

means for moving at least one of said member and said means for contacting said member in surface contact such that said means for contacting periodically seals the length of said slot during said movement over the surface of said member;

actuator means and means to couple said actuator means to a source of air under pressure, said actuator means, upon being activated, causing a burst of air to be released from said source and forced under positive pressure through said slot, and programmer means responsive to the sealing of said slot for activating said actuator means when the length of said slot is sealed.

2. The apparatus of claim 1 including means to move at least one of said member and said means for contacting said member periodically into and out of contact at said slot during the operation of the apparatus.

3. Apparatus of claim 1 including receiver means at the end of said slot for receiving material flowing through said slot.

4. Apparatus of claim 1 wherein said actuator means in cludes a conduit within said member capable of connecting air pressure means to said slot;

valve means interposed in the conduit;

means to open said valve means.

5. The apparatus of claim 1 further including switch means to activate said programmer means, and

register means associated with one of said member or said means for contacting said member to energize said switch means.

6. The apparatus of claim 1 wherein the actuator means for forcing air through the slot is positioned at the end of the slot to force air through the entire length thereof.

7. Apparatus of claim 1 wherein said actuator means includes a piston valve within said member.

8. Apparatus of claim 7 including means to activate said piston valve external to said member.

9. Apparatus of claim 8 including means to move said member and wherein said means to activate the piston valve is responsive to the movement of said member such that the piston valve is activated when the slot in the member is contacted by said means for contacting the member. 

1. Apparatus for removing accumulated materials including a member having a slot in the surface thereof; means for contacting said member at the surface thereof; means for moving at least one of said member and said means for contacting said member in surface contact such that said means for contacting periodically seals the length of said slot during said movement over the surface of said member; actuator means and means to couple said actuator means to a source of air under pressure, said actuator means, upon being activated, causing a burst of air to be released from said source and forced under positive pressure through said slot, and programmer means responsive to the sealing of said slot for activating said actuator means when the length of said slot is sealed.
 2. The apparatus of claim 1 including means to move at least one of said member and said means for contacting said member periodically into and out of contact at said slot during the operation of the apparatus.
 3. Apparatus of claim 1 including receiver means at the end of said slot for receiving material flowing through said slot.
 4. Apparatus of claim 1 wherein said actuator means includes a conduit within said member capable of connecting air pressure means to said slot; valve means interposed in the conduit; means to open said valve means.
 5. The apparatus of claim 1 further including switch means to activate said programmer means, and register means associated with one of said member or said means for contacting said member to energize said switch means.
 6. The apparatus of claim 1 wherein the actuator means for forcing air through the slot is positioned at the end of the slot to force air through the entire length thereof.
 7. Apparatus of claim 1 wherein said actuator means includes a piston valve within said member.
 8. Apparatus of claim 7 including means to activate said piston valve external to said member.
 9. Apparatus of claim 8 including means to move said member and wherein said means to activate the piston valve is responsive to the movement of said member such that the piston valve is activated when the slot in the member is contacted by said means for contacting the member. 